title: Changes in leukocyte populations of cows with milk fever or displaced abomasum after calving.
abstract: Most of the metabolic diseases of dairy cows occur within the first 2 wk after calving, and cows with a metabolic disease are prone to infectious diseases. Although metabolic diseases are generally recognized as a risk factor for infectious diseases owing to the associated decrease in immune function, the difference in immune status between cows with milk fever (MF) or displaced abomasum (DA) during the lactation period has not been clarified. Therefore, the peripheral blood leukocyte populations in 38 multiparous Holstein cows from 1 herd were analyzed after calving. The cows were divided into 3 groups according to health: 21 cows that remained clinically healthy throughout the experimental period (control group), 9 cows that had MF on the day of calving, and 8 cows with an onset of DA within 4 wk after calving. The T- and B-cell numbers were lowest at week 0, and they increased gradually after calving. There was no significant difference between the 3 groups in the number of each subset of leukocytes on the day of calving, but the number of CD8⁺ T-cells was significantly lower in the MF and DA groups than in the control group at week 1. The numbers of CD4⁺, CD8⁺, and WC1⁺ T-cells tended to be lower in the DA group than in control group from weeks 4 to 12, a tendency not observed in the MF group. These data suggest that when cows have DA around the time of calving, their lymphocyte numbers remain lower until 12 wk after calving.
authors.affiliation: School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan (Ohtsuka, Tomioka); Agriculture Research Department Animal Research Center, Hokkaido Research Organization, Shintoku, Hokkaido 081-0038, Japan (Fukuda); Ishikari Agricultural Mutual Relief Association, Ebetsu, Hokkaido 067-0055, Japan (Kudo); Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan (Koiwa); College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA (Kimura).
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Ohtsuka
authors.forename: Shigeo
authors.initials: S
authors.lastname: Fukuda
authors.forename: Katsunori
authors.initials: K
authors.lastname: Kudo
authors.forename: Michiko
authors.initials: M
authors.lastname: Tomioka
authors.forename: Masateru
authors.initials: M
authors.lastname: Koiwa
authors.forename: Kayoko
authors.initials: K
authors.lastname: Kimura
mesh_terms: D000018:Abomasum / Q000503:physiopathology*; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry / Q000662:veterinary; D006996:Hypocalcemia / Q000097:blood / Q000276:immunology*; D007774:Lactation; D007963:Leukocytes, Mononuclear; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*